Cinching mechanisms are commonly used now in connection with vehicle doors. They operate to fully latch a door that is only partly latched as a result of someone closing the door without sufficient force to effect a fully latched (i.e primary latched) condition. The cinching mechanisms essentially pull the door to a fully latched condition with some type of motor-powered mechanism.
In a common case, the mechanism includes some driving means for engaging and driving a door latch fork bolt from a partly-latched to a fully-latched condition. Once this occurs, the driving means then disengages the fork bolt to permit unlatching. If the driving means fails to disengage the fork bolt, there must be some way to override the driving means to allow the fork bolt to rotate to an unlatched condition wherein the door can be opened.
There are several manual override mechanisms now in use. But most involve complicated arrangements having several parts. One such example is shown in U.S. Pat. No. 5,639,130 to Rogers et al. This assembly works well, but vehicle cost and weight can be reduced by devising a simpler design with fewer parts.
Another override mechanism involves a cable-driven cinching mechanism that is similar to the cinching mechanism in the present case. The manual override mechanism includes a separate linkage between the gear lever and the latch handle assembly. This linkage allows unlatching even in the odd event that the drive mechanism fails to return to a neutral position. The linkage basically disengages the cinching gear and the gear lever to allow free movement of the fork bolt even though the cable continues to hold the gear lever down in a driving position. But the linkage presents packaging problems for a door environment that can be crowded with other parts.